VictoryMBA
It wouldn't make sense to ask my boss to start thinking about letters of rec prior to the release of the 2009 application would it? Keep in mind I want as less stress as possible, but if there is nothing concrete for him to look at and complete, he won't do anything.
There are no guarantees in life except for death, taxes and some sort of snafu by your recommender. I'd suggest a soft deadline to them. If you need it done by 11/15/08. Tell them you need it by November or end of October.
Also, let them know that there is a good amount of work involved. You can't write the reco for them and you will be supplying certain info about yourself, why mba, resume, goals, your fit w/school etc. You will be providing your recommender with a package.
So early is always best and if you can get the previous year's form, even better.